Test 4

Question 1

Is metabolism the process by which your body converts food into energy?

Answer 1

Yes

Question 2

Does metabolism include all the chemical reactions in your body that keep you alive?

Answer 2

Yes

Question 3

What is the difference between catabolic and anabolic pathways?

Answer 3

Catabolic: Break down large molecules into smaller ones, releasing energy. Anabolic: Processes that build up large molecules from smaller ones and use energy

Question 4

Define free energy

Answer 4

A system that is available to do work

Question 5

What is the difference between an exergonic reaction and an endergonic reaction?

Answer 5

Exergonic: chemical reaction that releases energy and happens on its own without needing extra. Endergonic: chemical reaction that absorbs energy and needs energy to happen

Question 6

In what reactions can a positive/negative free energy value be found?

Answer 6

Positive: endergonic reactions. Negative: exergonic reactions.

Question 7

What is the general equation of aerobic respiration?

Answer 7

Glucose + Oxygen to Carbon dioxide + Water + Energy (ATP) (C6H12O6 + O2 to CO2 + H20 + Energy (ATP))

Question 8

What is the first step of aerobic respiration?

Answer 8

Begins with glycolysis which occurs in the cytoplasm. This is where one molecule of glucose is broken down into two molecules of pyruvate

Question 9

What does the break down of one molecule of glucose into two molecules of pyruvate create?

Answer 9

A net gain of 2 ATP and 2 NADH molecules

Question 10

What happens next in the oxidation of pyruvate in the mitochondrial matrix?

Answer 10

Each pyruvate is converted into acetyl CoA, releasing one NADH per pyruvate

Question 11

What happens in the Krebs cycle (citric acid cycle)?

Answer 11

Acetyl CoA is fully oxidised, releasing two molecules of CO2 per cycle

Question 12

What does the Krebs cycle generate?

Answer 12

2ATP, 6NADH, and 2FADH2 per glucose

Question 13

Where are the high energy electrons from NADH and FADH2 passed to?

Answer 13

The electron transport chain in the inner mitochondrial membrane

Question 14

Does the energy in the electron transport chain then pump protons across the membrane, creating a proton gradient?

Answer 14

Yes

Question 15

What is the final electron accepter?

Answer 15

Oxygen, forming water

Question 16

What does the proton gradient drive, and how many ATP molecules does ATP synthase produce at chemiosmosis?

Answer 16

Chemiosmosis. 26-28.

Question 17

How much ATP is produced in glycolysis, oxidation of pyruvate to acetyl CoA, and Krebs cycle respectively?

Answer 17

Glycolysis: 2, oxidation of pyruvate to acetyl CoA: 0, and Krebs cycle: 2

Question 18

How does DNP affect chemiosmosis?

Answer 18

Disrupts it by making the inner mitochondrial membrane leaky to protons

Question 19

What does disrupting chemiosmosis prevent?

Answer 19

Prevents the proton gradient from being used efficiently by ATP synthase to make ATP

Question 20

Does energy get released as heat instead?

Answer 20

Yes

Question 21

Define electron carriers

Answer 21

Transport electrons during cellular processes. Common electron carriers include NADH and FADH2

Question 22

What does being oxidised and reduced mean?

Answer 22

Oxidised: accepts electrons and a hydrogen ion to become reduced. Reduced: carries electrons to the electron transport chain

Question 23

What are the oxidised forms of the major electron carriers?

Answer 23

NAD+, FAD

Question 24

What are the reduced forms of the major electron carriers?

Answer 24

NADH, FADH2

Question 25

What is the general equation of photosynthesis?

Answer 25

Carbon dioxide + Water + Light energy to Glucose + Oxygen (CO2 +H20 + Light energy to C6H12O6 +O2)

Question 26

What are the two main stages photosynthesis consists of?

Answer 26

Light-dependent, and light independent reactions (Calvin cycle)

Question 27

Where do light dependent reactions happen?

Answer 27

In the thylakoid membranes of the chloroplasts

Question 28

When chlorophyl absorbs light energy, where do electrons get passed through and what does this lead to?

Answer 28

Through the electron transport chain, and to the production of ATP and NADPH

Question 29

Do water molecules split during this process, replacing the lost electrons, and releasing O2 as a byproduct?

Answer 29

Yes

Question 30

Where do light independent reactions occur?

Answer 30

In the stroma of the chloroplasts (the fluid surrounding the thylakoids)

Question 31

What do light-independent reactions depend on if it is not light directly?

Answer 31

The ATP and NADPH produced in the light-dependent reactions

Question 32

Describe the Calvin cycle

Answer 32

CO2 from the atmosphere which is fixed to a 5-carbon molecule is broken down into two molecules of 3-PGA. This is then converted into a three carbon sugar, after which some exit the cycle to form glucose and other carbs, while others are recycled

Question 33

What are the some of the key products of Calvin cycle?

Answer 33

NADP+ and ADP, which return to the light-dependent reactions to be recharged

Question 34

What kind of reactions are photosystem II and photosystem I both crucial components of?

Answer 34

Light dependent reactions of photosynthesis

Question 35

What do all photosystems help to accomplish?

Answer 35

Capture light energy and facilitate the production of energy-rich molecules like ATP and NADPH

Question 36

What is PSII responsible for?

Answer 36

The initial step of absorbing light energy and using it to split water molecules into oxygen, protons (H+), and electrons. Also helps produce ATP by creating a proton gradient

Question 37

What is PSI’s function?

Answer 37

Absorb light energy and use it to re-energise the electrons that have passed through the electron transport chain

Question 38

Are these high energy electrons then transferred to NADP+, reducing it to NADPH?

Answer 38

Yes

Question 39

What is Rubisco?

Answer 39

An enzyme that is essential for turning CO2 from the air into organic compounds that plants can use

Question 40

Define metabolic pathway

Answer 40

A series of chemical reactions that happen inside a cell, that help a cell get energy, build things it needs, and break things down

Question 41

What are the two ways ATP is formed?

Answer 41

Substrate-level phosphorylation (occurs in glycolysis and the citric acid cycle), and oxidative phosphorylation (occurs in electron transport and chemiosmosis)